Rats and Mice
These guys can make excellent pets for people with little space for larger pets, are somewhat mobility challenged, or don't relish the idea of having a larger pet to care for. They can be very affectionate and rarely bite if socialised properly as youngsters. They do like company, so do better with a mate (of the same sex), though introducing adult males is not recommended.
Unlike other pocket pets, mice and rats have permanent molars which don't continually grow, and incisors that do. The yellowing of the incisors is natural and is associated with iron deposits and not decay as we would think.
Mice and rats love to chew on things, so providing environmental enrichment to allow this natural behaviour is a must. Providing empty boxes, sheets of paper, ladders, wheels, and bolt holes all encourage exercise and behaviour. Multi level housing encourages exercise, and flooring can be mesh, but must have sufficient (absorbent) substrate to prevent foot problems.
Cages should be cleaned regularly to prevent ammonia buildup, but excessive cleaning can be stressful to the animal by constantly removing scent markings. Mice in general tend to be smellier than rats, and males more than females (no surprise there!)
Diet should consist of high protein pellets, rather than a predominantly seed based mix (which can promote obesity). Fruit, nuts, vegies, pasta and cheese should be occasional treats, but can be useful for training. Water should be given from a dripper, or a heavy bowl that can't be overturned, and it should be changed daily.
Mice and rats can breed from 4-6 weeks of age and if disturbed too much after giving birth, or if the temperature or bodyweight of the dam is too low, can cannabilise the litter. Excessive handling can also lead to cannabilism, or desertion of the litter. It's recommended not to handle the babies for 1-2wks. Desexing of males is recommended if breeding is not desired.
Have a look at the video below to see just how trainable these guys are. They really do have their own personalities!